Card warp is a classic routine, performed by many of the worlds top magicians including David Blaine

You forld a card in half lengthwise, so that the back design shows. A second card is folder in half across it's breadth. As the inner card is pushed through the outer card, it VISIBLY TURNS INSIDE-OUT! The face of the card now shows. The cards can both be handed out for inspection. The trick can be instantly repeated!

You really need to watch the demo video to see just how mindblowing this magic trick is!